hershey



H. E. HERSHEY, "AUTOMATIC DISTRICT TELEPHONE SYSTEM.

APPLICATION Hm) SEPT. 4, 1920. I I E 15,073.

-5 SHEEIS-SNEE1L zz'farrg Efi'ershey Beissued Mar. 29, 1921.

H. E. HERSHEY.

AUTOMATIC DISTRICT TELEPHONE SYSTEM. I

. APPLICATION FILED SEPT. 4. 1920. Bmssued Mar. 29, 1921. 1

. s SHEETS-SHEET 3- III-W En.rarz ur:-

I H. E. HERSHEY. AUTOMATIC DISTRICT magnum: svsnam Reissued Mar. 29, 1921.

APPLICATION FILED SEPT. 4, 1920.

Inusn ur-- n. E. HERSHEY. AUTOMATIC DISTRICT TELEPHONE SYSTEM.

' APPLICATION mm smm 1920.

15,073. 5 SHEElS-SHEEI 5.

Reissugd Mar. 29, 1921.

UN -Tao STATES.

PATENT. o Flcs,

mm! a. n, orwmzw'un, mass. sssroxon .ro Auromnc unscrew comm, or caroaoo,mmozs, a conrourxon or rumors I hummus ms'rmc'r rnnnrnomn 518T;

lpeciflontion or leilsuedlctters Patent. R i d 29, 1

7 ori inal Io. 1mm, um comes as, 191$, ler1al Io. use ot a, 1914. Application In reissue filed leptember 4,1030. s mi It. seems.

Toalliohomitmag cmem: I Be it known that I, E Hsnsrmr,

a citizen ofthe .United'Stites of America, and resident of Whitewater, inizthe county of Butler and State of- Kansas, have invent;- ed certainnew and useful Improvements in Automatic District Telephonesystems, of I which the. following is aspeeification.

My invention relates to autolmlti'c "district telephone stems-that is iii which the subscribe oflices or exchanges.v and trunking'conneclishment of a connection between 3 sub--; scribers lines which terminate in difierent exchanges.

The object of my' invention is to provide improved trunking apparatus for establish. ing connection between lines in such a sys- -A A 1* a "oflices. Ina system of this character, when tem, an'dto Erovide meanswhereby'a conis local to any exchange can rom one exchange to another, apparatus at a main or central oflice is automatically brought into use to establish such connection. B my invention I provide a repeat- ,mg mec amsm which, through its 0 era:

a. made thro chm tipni, determines whether a call he! be ugh the apparntus'local to a branch office, or whether the call 'shall 'pass through to the apparatus at a main ex Thus' if a subscriber'wishes to call anot er subscriber in the same exchange, the

repeater operates to eliminate-the apparatus at the mam oflice and to permit the call to p ss throu h apparatus local to the sub-ex- .I however, the subscriber wishes subscriber whose line terminates in apfiaratusiat the main exchange.

invention will be more clearly undermoi by reference to .the accompan ing drawings, in which-I have. illustrate the em 10 switches of well-known types.

a lift rawin 'scribe r (o line is connected with the line of the called Figure 1 represents dia-' of the system shown in Fig. 1.

tail the trunking arrangement of a portion 1 igs.i3, 4, 5 and fi-show a cgmpl'eteconed herein isam-ultiple oflice or district sys V 'comp3risin%) a plurality of exchange rs lines tenninatein difi'erent oilices A, A A B ,B etc. With tolthe trunk connections between of- .tions are provided between these diflerent exchanges in order to provide for the 'estab -i fic'e's atheseare divided into two classes. The

-veflicegfA B, C, and D are each connected w th eachfof the others by a separate set of trunk lines, and for convenience these .oiiices will be designated as main ofiices; The ofiires 4, A' 'B', B, etc., are each connected by trunk 'lineswith only the nearest main oflice A, B, C or as the case may be. The offices B, B etc., .will be termed brunch 'callingvs u bscribers line is connected through the medium of the suitable apparatus at'his ownofiic efofiice withu trunk line leading direct] to the ofiice of the called sube C), at which ofl'ice said trunk subscriber. If a subscriber of one of the branch ofiices (ofiice A, for example) wishes to call aisubscriber of some other oflicc. he must first" obtain connection withm trunk line. leading to his main office (oiliceiA). .At

this office connection may be made with a a trunk line legldilrii i to the oflicelof the called subscriber provi ing the called subscrihers line terminates in "one of the main saves,

or in anotherbranch oflice (such as theofiice A) which is connected with the same main ollice as the calling subscriber. If the called subscribers line terminates at a branch oflice same reconnection with a telephone system (oilice 03 m example) ofa second main gflice (ofiic'eC), the calling subscriber, after (oflice A), mustthen obtain'connection with a trunk line leading to saidsecond main ofice (Ofiice C), "and then, through the meobtained connection over a trunkline NVlth apparatus in his" own mam oflice dium of apparatus at said second ofiice to be connected with "a; trunk line leading to the,

branch office (oflice'vC) "of the mcalled subscriber, where the connection "is finall coin pleted. Following out this general plan, if. ,3 a subscriber of a: branch ofiice glesired to ob- 3 oflice withi .wl'iich his branch oflice .is con- -with a second trunk line' leading vback from nected; andwould then obtain connection the main oifice to the" branchfofiice, from which saidfsecond triink line connection would finally be completedwith tlie called subscribers line. Byiny invention, how-' ever, the trunk linesleading from the branch emcee) the main oilice and back" from the main oflice to the branch one from connections between the --the same'branchofiice, said connections 'bein established entirel b a "'aratuslocal g g y situatedlinflthe main oflice, orsotne ofwhich Referring to Fig.2, the method oft a ying out my invention in general as'g foh lows: The apparatus-finclosed within the dotted lines reEresents" the apparatirs 'of a is assumed to'be local toja main office. There are shown iiipthis figiire'twogroups of sub scr'ibers substations T and T, the line conductors of each of which terminate inlan individual trunk selecting .or preselector switch E at the'branch oflice. "For thevpurpose of being called, those lines terminate f in the. banks, of a, plurality of connector switches F. These connector switches are represer iedherein by small circles, the three t which lead to socalled secondary trunk- Mselecting switches H. The switches H have resented as being multipled together, itis'to 1 access to trunk lines t :which-lead to-firstz selectors in themain oflice. Associated. with the main office therev are shown two- ;groups of subscriberssubstations T and T 9', each of I which groups isprovided ,with a group of reselecting oriline switches at the central 0 ce for-calling purposes, and with connectionsin the-banks of a groupoiconnector switches F for being called. Each of the groups of line switches E has access to a grou of first selector switches I, which first se ectors in turn have. access to second selectors J. Although, the bank contacts of all the first selectors, shown'inFig, 2 are repbe understood that this figure is only diagrammatic, and any known or desired multi-- second selectors arerexcliided subscribers "of ilc -t-he remaining apparatus tend pling arrangement of the selectors may be employed. As shown herein, the first level 'oflices, where said trunk lines would ternii naterin second selectors. In like manner, the main oflice is through the first selectors of the other'main leve'lsof the second selectorswl have access provided with groups of H i which ,are, accessible Q of the selectors has access over trunk z lines t to-second selectors J in the same I exchange. The remaining two levels shown ofiices in thesystem. The third andsixth;-

to trunk lines leading to line switches Z in 5 the branclrofiice, which turn have access through the-medium of connectors]? to the subscribers lines T 'and T5; The remaining levels of the 'same group second selectors have access to connectors having access to the subscribers lilies in the inain ofiice. The

remaining groups of secondselectors may have access to connectors all of which are are situated ina branch ofiice/and some in the main office, or in any manner desired; In each ofthe trunk llIleSi which lead from the; subscribers individual switchesEto the secondary switches I-l there-is a switching may'operate to connect the trunk line. which v has been seized by a-subscri,bci"s individual switch with a connector in one :or the other and T: 1, v E

In general the operation of the system to select atriink' 'l iiie leading to a secondary switch H,,which in turn operates to select an idle first selector 1. The subscriber operates his calling device to cause the selected first,selectorv to extend connection to an idle second selector in the section or division of the exchange to which the calledsubsci'iber device L which, under certain conditions, V

of the groups of'connectors which have ac- 5 cess to the branch oiiice subscribertgroups T behings. The selectedsecond selector is then operated to' exte'nd the coiinectionto an idle ,connector' sw tch which has access to the group of subscribers to which the'called subscriber belongs,'which connector is then operated to establish connection withv thecalled subscribers line. Assumingnow that the calledsubscriber is in'the same branch o'flice as the; calling subscriben. Under these conditions,when the calling subscriber operates his calling device, to cause the second selector to establish connection with a" connector switch, the ,switchingapparatus L, in the trunk line which has been seiied by the calling subscribers line switch, operates to exthe 'connection'directly to one of the trunking r to illustrate mg ,and an 1m subscribers lines a and T, depen ng upon the group in which the called subscribers line is situated. In other words, when the has progressed to the stage of elim natlng all the sections except the section towhich the call is to revert, then the switching apparatus L disconnects the-call from the trunk line leading to the switch H 10 and switches the call over to the local connectors F.- When the apparatus L thus opcrates to extend the connection to a local connector, it causes the secondary switch H which was previously selected, as well as all 15. the selectors which have ,been operated 1n the main office, to be released and the connection is therefore confined solely to the branch oflice.

Theapparatus with which I have chosen invention is of a well-known type and :iss own ,in patents of the prior art, andnit is therefore thought necessary to show only such details of construction as are necessary to bring out "the novel feature.

The telephone substation T (Fig. 3') comprisesthe usual receiver-2, transmitter 3, switch-hook 4,"? r 5 and condenser 6. an automat c substation, it is also provlded'with a suitable calling device or so impulse transmitterwhich is represented air of impulse springs 7 and 8 se wheel 9, which latter may y the callin subscriber through herein by a operated the medium of'afin er ole dial (not shown) as to cause the imp springs to be opened a'number of times corres ending to the digit which it is desired to v The subscribers individual switch E QFig. 3) which may representany of the w'switches b I 1 shown in Fig. 2, is of the general type of switch disclosed in British patent to R. W. James No. 26,301 of 1906, being of the more particular form shown in British atent to"A. E. Keith No. 1419 of 16 1910. 'l u 's line switch, as is well known, is provided with a movable plunger which, when idle, is always maintained 0 posits the bank terminals of an idle trunk ine by a so-called master switch. Upon the o raso tion of said switch its plunger 18 force into v springs of said trunk line to connect the subscribers line therewith; The switch Z is similar in allrespects. to the switch E.

The master switch N is eral type as that disclosed No. 26,301 of 1906, referred to above, being, however, of the particular type disclosed in saidBritish Patent No. 1419 of 1910. The

the terminal of thesame genfunction of the master switch, as is well known, is to maintain the phmgers of all idle switches in position to minals of an idle trunk line.

The apparatus shown at L (Fig. 3) is repeater comprises a verticall switch ,sha

, and 1130f the levels in British Patent and the le've engage the tcrthe central station. In a local connection this device operates to free the trunk line leading to the main oflice aid to divert the call to the proper local switches for com let- 3 ing the desired connection. This switc and rotatably movable switch shaft 0 not shown)- which carries the wipers 65, 77, 112 and 113 In a call from the and is controlled by the vertical magnet 59 and the rotary magnet 64 in the manner shown in United States Letters Patent No.

815,321, granted March 13,1906, to Keith,

Erickson and Erickson, for improvement in Selector Switches, These operations are controlled through the medium of a doublewound line relay '18 which is connected with the line conductors through the sprin of a reversing relay 51. wound and is so. adjusted that it is o ratively energized only when bothwin5i ngs are energizedin the' same direction. The line rela' the tru conductors for the pur ose of repeating impulses to the main excliange in a manner. to be hereinafter more plained. The magnet 74 is the usual .rc-

ease magnet for restoring the switch shaft and side switch the release of, the

connection. However, the release ma et is adapted to release the tion, rather than upon the dee'nergization thereof as shown in'said selector patent. This release et is connected in series with a double-wound relay'73.- The switching repeater L is also provided with a socalled side switch similar to that shown in said selector patent, together with two relays 28 and 58' which are slow acting-that is, relays which deenergl'ze slpwly after their fully ext immediately upon energize The relay 51 is ouble 18 controls a second bridge across to normal position upon I energizing circuits have been broken. There are ten rows or levels of bank contacts for each of the wipers 65, 77, 112 and 113. The

bank contacts accessible to the wipers 112,

corresponding tothe branch exchange in which the repeater L is located are multipled between banks, while I the contacts in each level of the bank accesr 77 are connected together,

sible to the wi which correspond to the groups of connectors in theibranch exchange are connected to the left hand sprin 76 of the rela; 73 of each re ater L. glso' in the ban associated wit the wiper 65 the 5 first contact in the level corresponding to the main oflice with whichthe branch office is. connected is connected. with the spring 71 of the relay 73. For example, if the num hers in the hrsinch oifice begin Yivith the cli it energizfzition thereof, as shown in said selec- 5, whenever the "dial/isfii'pe ted [for t to! patent. The relays 55 and 80. are. slow first digit 5 the wipei'sl will be ii'ii'sed" to the acting h i 1 fifth levehand \ipon cnttin" in upon the v 'The connector switch F, which may cor- I I {first contact in said level wil close a c gemt respond to any of theconnector switches Whichwill ciilise the elease of this switch at' the same time cziusiii 1, plaeedj 1| pen] all the coil the jwiper 77 which are con to nectdr' shown in United States tters Pats accessible to eji't No. 815 176., grahtcdMarch 13, 1906, to l nected with the Keith, Elieltson and'Erickson, being Inod1-' ring 76'. If theffi 'st dlgit celled by the lied, however, 111 orgl'e to operate in a two: i fi s Wemtifiil f the diifll is other thfin 5, w re system. The switchcoxnpr'ises among theswitcli will not be rele'fised, will other details a'bank ofcontacts arranged in lei'el to which it has beeh raised; but gagged by a set oflwipersi 'llfi, 117 and 118, this level be one whicl i lezids' tothe local" which wipers ere carriedby avertlcally and inhect 1S, th switching relay 174 l n rotatably movable shaft (not shown) wh ch be operated 011 the 're I there is nogi-ound on fthe spring 76, as the m" I f ay 173 h 0' ne g z d by e {switch iscontzolled by the private magnet switch "releasing from the levels It 122 i th well-known' manner; The usual d) oted here flliliit'shfillld, 16 j L release magnet 123 is adapted to releasemthe 'be resting upon a bank contactleadi lg :"1 wit h h fl; immediately ugon energizaconnector, ondthe switchingrelay 1141:; not ti i, ther than by the i ene rgizedgithe contact m eiinergization t is; thereof, as shown in said connector patent; mndebiisy', for thejswitohf iiqs nofi p fl e At 124 is; show-n the ring er'relay 'by" means l l u p its P i a l l fl' i e of which ringing currenti= is projected onto fW P H- S n th r P 'A e fii'gt the called line. The relays 'l43and226 are l fifi ii f gm conhwtovs' all respects. to thelconnectorF'.

T uP h th first? le (3011mm? L hl dividual .witch" E? are in all respects theiU' W i 'Q F elay 174 m -i same as t e telephone substationfl" end the ,,ffdi1e to the ground now, upon the gwitf -h E fIwFig- 3) c in qe.

The secohdal'y Switch H 5.)," i h ing c'uritent generator and at Q is shown r p d t o e bf u t g H; a busy ti mnn machine; while the batthe same in principle as the subscribers ;1n t fi gx I fdiiidual'switchlhf, bemgf soinewhet sun- ]f r gmti th i t l Pl di f v lh i that iitilisnnot I P dQ and: folytalking pu poses Tlabfi ith in 0;, tre y rma sf i Havihg given. eneraldescription of th Swi el gs' i g p' w i (nsystemfiand'appar tus] in connection with. l j iQ yi i S t h which {it has been chosen to-illu'strate the 'Sim h lfiQT the w t h invent n disclosed herein, there will now h "S i h 1' i F1 1 be givgn a more or lessdeteiled description him .Y p es nt *i y sp t switches of tlieaioperations by which the i145 connections t ,IQO g- 2), fire of he: g e p t P of are established 'betweenlwthe; 'v arious subk Q Q O T. w h s d 5 d n said etters scribers," Since thevapp'aratus shown herein iff l ifm N 15, 2 above referredto,.; be-fi is in general well known. in the; art, and is i v n Bri ish ri fi 'n N -j 0 1910, .hereinreferred toi it is not'tho1 ght,.ne'cessary to nboiye refelzrjed'to, sees to operate in a twodescribe; its operation in deteilf-herein. It

v Bejfieriting toJtheselector Ileach of these T o'fl themain ofiice out oftwhich' letter H @wifieps 95,598 and 99 which are carried by .called substation willfhe'as'sumed to be a. ertically end'jrotgitably movable-shaft a i tishown) is' controlled. ,by, the Upon lb? 5151111611 Q the Swim v P 'C i Q V The telephone substation Ti and the in ngsomeyvhat'modified,"howei er, as Shown 11115 in the pjublieationscherein I 1 i i chescom'prises. among other detailse. oflice the saidtbrench office operates. The."

fof fcontacts a 'mnged nrows, o leyels number of the .callingsuhstation will be 3 an adapted tobe; engaged by 'a, set of assumed to be'5600end'1the; numberof the i to rest u'p0'i1*the rst contact "in the rows or levels which are adaptedto be eno t' lfl i fim 5 isf controlledby the usu'al vertical and to magnets 120and 121. The usual side 1 At 0 1? g. 6) there is repfesehted a I'ingand 1X are for supglying current. ce appera wi i; system The customary side switch is ,wi'll first be explainedhow :i'ponnection is -likexi ise dispensed with; the-circuits being. extendeddfronithe -telephone snb'station Tf ",f-urthegjslightly modiiiedon this account. 1 of a, branch oflicelto a telephone*substation i 1 i L V usujel vertical fandyrota ry magnets '79 and callingsubstation, a bridge is formedacross $22.7,Thefusualrelease magnet Sis-adapt the milling line "througlhthe transmitter 3 releas'e the switch shaft immediately and receiver 2 b'y'thec upon fenerg zation, rather vthan .by 1, the de hook springs, whe 'ebTy an enex gizingcircuit .osure of the switch-' s rings'42 and 43 to the selector I, while at is closed throug the line winding 209-61 the subscribers Switch E. The winding 209, upon energizing, attracts the armature 10, whereby-a circuit is closed through the 17anii16tot pull-in winding 11, which operates to .at-

tract the lunger arm 12 and cut-ofi armature 13.- he plunger arm 12, upon bein attracted, thrusts the plunger into its ban of contacts, whereby the line circuit is. extended through the springs-14 and 15 and the armature 13 operates to disconnect the winding 209 fromthe line. When the connectlon is extended to the switching repeater, a circuit is closed through its line relay 18, said circuit extending from'ground 'G' through the lower winding of'the relay.

18, relay springs 19 and 20, relay springs 21 and 22, line' springs 16 and 17 to and,

through the substation T,:line springs 14 and 15, relay springs 23 and 24, relay springs 25 and 26 and the upper winding of t e relay is to battery X. The relay 18, upon energizing, closes a circuit from.-

ground G through the front contact of the s ring'27 and the relay 28 to battery X.

e result of the energization of the relay 28 is the closure of a circuit extending from ground Gr through the springs 29-of the reay 28, springs 30 and 31. of the relay 174, private l1ne springs 32 and 33 and the holdmg winding 34 to battery The winding 34, upon energizing, serves to. hold the I a onder switch H (Fig. 5 springs 37 and switch E in its operated position after the line winding has bee'n disconnected from the line'and broken the circuit of the windin 11. A further result of the energization o the relay 28 is the closure of a circuit 'extending from ground Gr through the springs 29, conductor 35, windin 36 of-1the sec- "38 an the springs on a masterswitch (not shown) to battery X. The switch H thereupon operates to extend the connection through the springs 40 andv 41 and the e same time,by the shifting'of the spring .87, the winding 36 is connected with the battery lead through the hi h resistance wind- 80 .energization of the line relay 18 when'the ing 44, so as to reduce t e holding current of the switch -H".' A furtherresult of the connection is first extended thereto is the I closed for theline relay closure of a bridge across the trunk conductors 45 and 46, whereby, as soon as the connection is extended to the first selector 1, as above described, an energizing circuit is 47. This circuit eX- tends from round- 4 through the lower winding of t e relayv47, springs and 49, sprin ,43and 42, conductor ,46, coil 50, the

rightand winding of the relay 51, springs v I 52, conductor 45, springs 40 and 41, s rings 58 and 54 and the u per winding of t e re lay47- to battery The relay 51 is not e switching repeater L, while 3 hereinbefore described, whereupon the operativolyenersiudst this t m because only one Wllldlhg has cu en fl g through it. The relays! lclosesssa circuit through By 0 i l w The foregoing operation takes place mediately upon the removal of the receiver from the awitch-hook at the call ng st upcn e e g i g,

t. e slow actlng re tion. The calling subscriber nowbperates,

. his callin device in the usual manner. fo

the first igitt of the called number whereby the substation impulse springs 7 are ac arated fiye tunes momentarily. Each time t e substation impulse springa'are separated, the line relay 18 of the switching re-. Beater 1s momentarily decnergized. The

56 and 57, relay 58, vertical magnet 59 and the side switch wiper 60 (in first position) to battery X. The vertical magnet 59 receives five impulses over this circuit and o erates to raise the shaft wipers opposite t e fifth level of bank contacts- The slow acting relay 58 is energized by the first impulse which is transmitted through itand remains in its operated position until after thelast impulse is delivered for the digit. In it's operated position the relay 5 8, by'placing the springs 61,,incontact, short-circuits the "and 8 coil50 and the right-hand winding of the l I relay 51, so as to remove their resistances from the circuit of the line lay of the selector I',while impulses are 'ng transmitted through it. The closure of the springs 62 completes an energizing circuit for the private magnet 63. Upon the breaking of this latter circuit when the relay 58 deiinergizes after the last impulse for the digit is delivered from the substation, the private magnet'63 deiinerg'izes and permits the side switch to pass to second position. The side switch wiper 60, upon passing to second position, closes a circuit through the rotary magnet 64, which thereupon energizes and rotates the shaft wipers one step, upon the first contact in the fifth level. The wiper 65 will meet with no guarding potential upon the first contact of the fifth level, as

nvate magnet will deinergize. At the time that the springs 67, and69 ,are in engagement, a circuit may sbetraced from ground G through the springs 67, 68 and 85 ne' relay 47-01 the in any way nk contact springs 71 and magnet Hand gnet will energize over this circuit and operateto restore the shaft of the switching repea ailect ing the first selecor I. The

r'elay '73 will he energized in series with the pulses w lay47 ofthe first selector lhy the relay the switching'repeater cause five impulses to be transmitted through the vertiin-series witlrtheslow acting are lifted be tracedfr." from'ground G' through the spring 81 and springs 162, springs 82 and battery "release magnet and,

p upon operating, Wlll close a locking circuit an the lower winding of the battery X." The energization of the relay 7 3, by the bringing into contactjof the springs '76, places ground from ground- G .upon all ,the bank contacts accessible to the "per7 7 wh'ibhlcorrespond of connectors in the branch 'oflice. the engagement of the springspring' 71 2 places ground from upon the first contactin the fifth level which is accessibleby thewi-per' 65;: The five imhich aretransmitted to tliehline re- ,31', springs Also,

cal magnet 79 whereby the shaft wipers Thesaid circuit may back fcontact, 83, relaySO 'nd thevertical magnet 79 to a ts energizedipos n continuimpulses are being-transmittedto the vertical magnetj'througl andm its maintained energized position closesa circuit extending l for itself extend] "cnergizedan tl ground Gt throngh thesprings 87-, springs 88 ,01? normal springs springsfifi and fl the sprin s Bland 'thron gh X, l he relay 86'tobattery ing, forms al I a fmm groundG the springs 87 and 88, oif'normal'j springsDO and 91' and the relay 1. upon the deiinergizat n relay r the lie impulsei r e ,the relay 1 86, upd nei'g "I tliroa git net -92 is r so SaidIei'rcait extends from '89; springs and 91, ringsfiigand the ro-' cry X The-rotary the wipers 88 and I I tor to and through the switching repeater m ter to' normal, without for itself-from ground G through'the rings 29, springs 30 and to the groups 1 78 with the ground G.

The slow=actin relay. 80 .is

"ng. circuit r calling called number, I

wipers of the' switching repeater come to circuit of the rotary mag-j thetrunk h "more whether ornot the relay 86 remains ener- I gized. Theac'ircuit vill drops back far enough to close 88 and 94. The rotary magnet fore operate in a manner similar a buzzer to, advance the 'wi over the contacts, u'ntil te non-ground contact of an idle trunk is reached by the wiper 95 -whereupon the rela 86 deenerw gizes. 'l h'e relay 86; upon eenergizing, whether after one or several operations 6). the rotarymagnet, permanently breaks the circuit offsaid rotary magnet and closes the circuit of thelswiitching rela' 96 Said circuit extends fromgroundt through the springs 87, 89', sprin s 90 and'97 arid the relay 96 to battery The'relay96, uponenergizing, disconnects, the line relay 47 from theline and extends the line connection through the wipers The line relay 100'oi. the second selectorJ' -becomesen rgized over a circuit extending from s' bunv I of the relay I00,'springs 101 and'102, conheavy conductor to the, conductor '104, springs- 105 'a nd 10'6and the "ofq 'the' relay 100 to battery- .100, upon energizing, the slow acting relay fords a liolding- 'ground fdr therelay 96' to take the; ilace of; ground G3, which will 1 presently he removed. Sai from grouhdj (i conductor'l09, private Wiper 95, and.97 and the relay 96 tozbattery l The calling. subscriber now, operates'his device for the in. response to which the shaft rest; uponth'e first contact of the second level in the bank. 'Thc'second level being dead in' Q the branch oflice,yits firstcontac --be idle. .When the side'switch torfrepeater passes to third cuit is closed through the l of the relayl'il, but the rel opcratively energized atjth s,

ll alwa current *inqits vtwo'jwindings oppose each; 3

other) Ingresponseto theimpulses sent over lace its "shaftwipers upon nector;-

\ .leetor L; When the line has been x'tended "to theconnectoril", a circuit may etraced from ground G";throu gh the lower winding of the leltlygl25, springs 126 and 127 conductor 128. over the heavy conducof the rotary magnet again be closed as soon astits armature 'the springs will there to that of rs step by ste springs 88, off normal springs 98 and 99 to the second selector J- G through the lower winding ductor 103,'over the heavy conductor toa-nd through thejswitching repeater L, over the gkpper winding. The relay closes a circuit through P 107,2which in turn afd circuit extends 1 through the-springs 108,.

firings 90.

second'digit. 2 of the he relayISQthesecond selector co ntact of the Second level in and t0 extendthe lines tothe coir-- V p lathe; same manneras explained L, over other hes, conductor to the conductor 129, through't e springs 130 and a new holding I to IBI-and theup r'winding of the relay 125 to battery X, he relay 125, upon energizing, closes a circuit, through the relay 226,.

which in turn, upon energizing, affords a ground for the relay 96 of the selector 1' an the relay 132 of the selector rivate W1 r 135, springs 136 and 137 an role 1 to battery X. At the private wiper 1 5 a branch of the abovestraced c1r-. cult extends through the oif normal springs 188 s ri 139 conductor 109 private p and 97 and the relay 96 7 relay 18, opens the circuitof the line rela 125 a oorrespondin number of times; Eac

time the relay 125 is deiinergized, a circuit is closed through the vertical magnet 120. The

'' energize during the momentary inter vertical m'agn relay 226 being slow acting does notldetions of its circuit. The circuit through tl ie vertical magnet 120 extends'from ground 1 G through the, spring140. and its back con- The relay 148, which is included in the op-' crating circuit of the vertical-magnet, re-

'mains-in iteener ized positiorrduring the entire time that impulses are'being transmitted through it and operates to close the circuit ofthe private magnet 122 as follows: F roln ground G through the springs 145 and 146 and the private magnet 122 to bat tery X. After the last impulse has been delivered, the relay 143 opens the circuit of r the private magnet 122, which, upon deenergizing, permits the side switch to pass from first to second position. The movement of the side switch wiper 144 from first to second position transfers the battery con- [nection from the vertical magnet 120to the rotary magnet 121.

' The calling subscriber now 0 crates his calling device'for thelast digit the switching repeater L, by means of the whereby line relay 18,- opens the circuit ,of theline 'relay 125 a corresponding number of times. Each time the relay 125 is denerglzed, a circu'it'is closed through the rotary magnet extending from ground G through the spring I 140 andflits back contac n 142, rela 143, springs 1 7, rota? springs 141' a magnet in second erotary magnet .12! and t e .side switch r 144.

position) to batte X.

ficeivee ten impu over-this circuit and Said circuit may be traced from ground through the springs 133, conductor 134? The si ihstation calling device is now 0per-' ted for the third di 0, whereby the switching repeater L, y means of the line of the back-bridge relay energizing. closes a circuit through the ,trunk from the switching operates to-rotate the shaft wipers upon the line of the called subscriber. he relay 143 0 crates in response to the impulses for the digit in the same manner as for the revious digit, to causethe private ma et 12 to advance the side switch to thir position. By the engagement of the side switch wipers 148 and 149 with their third-position contact points, the line connection is completed with the called line. Upon the engagement of the sideswitch-wiper 150 with its third-position contact point, a circuit is completed through the cut-off winding of the called line switch.

The said 'circuit extends fromground Gr through the side switch wi er 150 (in third position), private wiper 11 and the' cut-off winding 151' to battery X. The cut-oi! winding of the called line switch, upon enerizing,-operates to disconnect the line relay rom the calledsubstation. The connection of ground G" with the connector private bank contact of the called line prevents the called line from bein seized by some other connector switch. the engagement of the side switch wiper 144 with its thirdposition contact point, the circuit of the ringer relay 124 is closed. Said circuit extends from ground G" through the interrupter 152, relay 124, springs 153 and the side switch wiper 144 (in third position) to battery X. The-ringer relay disconnec g the calling-line from thencalled line and across the called subscriber. The ringer relay is energized bridges the rin ing current generator 0 I line to signal the called 1 only intermittently through the medium of the interrupter 152. Upon the response of .the called subscriber his line is provided with talking current through the windings 154,'which, upon ringer cut-ofl' relay 155. This current 'extends from ground G through. the side switch wi r 150 (in third ositionksprin 156 and t erelay 155 to attery TE: relay 155, upon energizing, interrupts the circuit of the ringer relay at the springs-153 and closes a lockin circuit for itself through the springs 15 v independent of the spring 156.

he ene'rflgization of the relay 154 also reverses the ow of current in the repeater L. Since the current in the right-hand winding of the relay" 51'isnow reversed, the two windings help each other and'the relay 51 becomes operativtalyenergized, and in so doing reverses the-current in the line to the su ionT';

QjAfterthe conversation is completed, the

connection is by the hanging up. of

the receiver a the calling substation in the f following manner-:Whenthe receiver at the substation T is restored to the switch; hook, the separation of; the switchhooksprings destroys the energizing circuit of to I y 1 thisguer' edfconta'cnfcornpletes" a circuit the switching repeater iine relay 18 upongdeener zing "j through the sprin] '1: contact, springs .56 and .15

, springs 159, release magnet 74 and the axial springs 161 an 'H to return. to normal position. 18'opens the tiller .gizmg circuit of the re ay' 125 of thegonre say 226, upon denergizing,

euit through the release magnet 123 from springs 165 to, battery X. The release megnet, upon energizing, withdraws the retem ing pawls from the shaft and ts own in cult is broken at the'ofi norn'ml sprin' 159 position. The denerg-ization of the reley 28 also removesfiround G? from thepon ductor' 35, which. 1031s the secondarlatslwitlch 8 G- energization of the rela nector F'. The relay 125, upon denergrq. in opens'the circuit of the rela 226. he

ound G hrough thespring 140' and its ac'k contact, sprin 141 and 266, 03 nor-' the release magnet 123 to battery X. The 1 release .magnetQupon energizing withdraws "the retaining :pawls from the sh at theoflhormal sprlngs lfi'lewhen the shaft reaches its lowest position. Thedenergization ofithe relay22fi removes" the" holdin 1 thro exten ring from ground v :8 1-i2fand its back eontect,,springsf-I62, springs" repeater raises its shaft wipers to eposition? 82.,end i163, ofifhorrnal springs, 164 andthe 115 to battery {The reown circuit is e when. the. shift reaches its lowest position.

ner. The define v i from the bank.

through, the private wiper 117 side switch ground from the relay 132 of the selector and of thereliiyt96 of'the selector 1' The deenergization of the rel'ey 96 closes a circuith: the release fiiegiet 115, said circuit 7 through the spring relegsev magnet lease agne e the retaining removes the.holdi groundffmmthe hold-' ingwinrling 34 of t .e liIieswitch- EQ Upon the deiinergizutioh"'oflthe holding winding- 12 removes th'e'plunger n hwing'beehexpleineii-how siihseriber be a guiirriingpotentin-l the "connector "privateflbank Contuct; 'iust "asieijpleined in connection with the line switch The connecto from ground at the private'bank contact wiper 150 (in second position), springs 166 and ,relay '16, springs 169 and 146 ant] c oses t cir-Numedto be 530,0.

chineQ u. n the calling iihe by711iearls of ethe springs; 17 and the;.-side swit l1?'ViP9 148-: second position).- 1The relay 168111 89 forms" a locking circuit for itself. from battery X. T-The p e released in! preetieelly, the eme: menn'er as described above,"

Itwillnow be expleiheii hotf j' anieca;

'statie'n T (uotshowm of. .the sein ranch of ice-1;", The. number of thecelled tel phon .will-beeg Upon the removal the substation T theeetion. of'the linesw ch- E, the switching repeater Lfth 0n arysWItch-H', andthe first" sele'mtor I the-same as previously describeill Upon the operation .of the call device eftand its ownlcircuit is broken 'for'the first digit 5, the switchin ;repeete'rf operatesiito raise; its shaft wi erslto th fifth level endto then release t 'ere irdin -thus I n locking up 'the relay 73, as prejioulsl ex pleined. The ectionfbf the selector I i the same as previously;expleinedl' I The calling subscriber now operatesh s called number.

' ground at. the .=:bank' contact through ,Ithe

I 4 r I Inathis Way-the; privatemegnet establi. hes eonnec'tion'eniiisreleeses the same, r. will be energizednns long; astheWiper 165;is

passing over: busy.- contectsi, At thefirst tel-"y X.-

idle contact the circuit through the priv atc switch to-psi'ss .to; third position, .thereby -wingthefeircuit of therotn'ry magnet 64. i

A nifgit is: the: some as previouslyegrphtined. hen the side switchfof the switching remay betrecerl from "ground G" through the ground G through the o5: nornial; springs 171; springs 1.7?2:en '1 (-,J l y l sis'b iigs Y 169mm 146 and the p i a eme t 12210 V lingl s nbscriber, upon and 159 when the shaft. reaches its owest 'h erine the u y g replaces the i ei-veli'v" theswitches. are

11 18 extjnded from the. telepl one sub; I

of n'branch oflice to a telephone};

- mngnet'wil] bel brqkenend' the privete mam. 1 net, upon deii nerg zmg, willnllow the side riviite wiper 117, upon enggztgin'gi operation of .the selector J! for thisj peuter L passes to third position, a circuit springs It, bank contact 173 wiper 77,

h a e pe s the ircuit. 1 I 1 of he rotery magnetat the springs. 147 and there; pieces the busy current from the husyjna- 1 l 10 11) *ciilling devicefor, the s'econidigit' s f TASTE. result the swjt ching opposite the 'thirdlevel, from whichpoint, 3' v t idle contact in the said level -iofi'banks inthe following mannerafl. As'soon;

as the side Switch wiper 60 passes tefsec'ond I position; 'a ci'rcu'i-t isclosed through the mtax-y magnet 64,? which,,.upon energizingjfi ,tates the sheitrwipers one stepy end oloss, 0 1' attionbf;thef relay 281 'a .circuitthrough the'i f'yate; mngnet 'fiiilj L. 1".

Should the contact upon v vhich'the wiper 65 is rotated have'a'guarriing potential-iipon it, a circuit. .will beelosed extending iifrom switching relay 1 energized over the 'ductor 185, bank contact 186, wiper 65.

wiper 60 (in t rd'position) to battery X. The 5 rings of the relay 174 are adjusted to ma e contact with their front contacts before they. break contact with their back contacts. The relayO 174, upon becoming a ve circuit, operates to shift the callin line from the line relay 18 to the line re ay 175 of'the connector P. A circuit may now be traced from ground G through the lower winding of the relay 175, springs 176 and 177, conductor 178, wiper 113, springs 179 and 22, springs 16 and 17 to and through the substation T, springs 14 and 15, springs 23 and 180, wiper I 112, conductor 181, springs 182 and 183'and the upper winding of the relay 175 to'bat- .tery The relay 175, upon energizing over the above circuit, closes a circuit} through the relay 184. The relay 184', upon energizing, affords a holding circuit for the holding winding 34 of the line switch E and also places a guarding potential upon the bank contacts in the master switch bank which is associated with the connector P. This. holding circuit may be traced from ground G through the springs 184, consprings 187 and 31, springs 32 and 33 and the holding winding 34 to battery X. A branch of the above circuit also extends from the conductor 185 to the bank contact 188. A second branch of the above circuit extends from the springs 31 through the springs 75 and the lower winding of the relay 73 to battery X. The line relay-18, upon being disconnected from the line, deenergizes and opens the circuit of the relay 28, which in turn, upon deenergizing, removes ground G from the conductor 35,

which allows the secondary switch H to hook at the substation T' opens the circuit k of the line relay 175, which, upon denergizing, opens the circuit of the relay 184*. The relay 184, upon denergizing, removes ground G which causes the holding winding 34 to denergize and allows the line switch E to return to normal. ,The removal of ground G alsoopens the circuit of the lower winding of the relay 73, which, upon denergizing, removes ground Gr from the circuit of the relay 174. The relay 174, upon denergizing, closes the circuit of the re--.

lease magnet and the switching repeater re- -leases, as previous ex lained.

In the present disc osure the line switch 174 and the side switch nector switch, as is shown at P. As previously explained, when the connector P is busy there will be a ground potential upon the master switch bank contact 188; which corresponds to said connector; If the master switch U at this time happens toholdthe idle line switch plungers o )posite the trunk line leading to the switch l, it will operate in the known manner to carry said plungers opposite the next idle trunk which leads to another connector, similar to P. As is well known the line switch Z has access through its bank contacts to a number of connectors P, the master switch U being the medium for determining the idle and busy condition of said connectors. It will now be assumed that connector P is idle and that the plunger (not shown) of switch Z is standing oppositethe trunk line shown leading to said connector. In responding to-a connection from the main exchange the switch Z will operate 'to thrust its plunger into the bank of contacts thereby extending the connection to the connector P. The operation of Z is similar to that explained in connection with the line switch E, The line relay 175 and release 'relay 184- are thereupon energized. 'The relay 184" upon energizing, ex-

tends a holding ground from G through springs 184, bank springs closed by the plunger, and the holding or cut-ofl' windin of said switch Z to the battery X. g branch of this circuit extends to contact 188 to cause the master switch to move the remaining plungers away from the seized trunk line. Another branchof this circuit extends over conductor 185 to the bank contact 186 of switch L, to prevent said switch from seizing connector P as long as it is thus connected with switch Z. The calling subscriber then operates the said connector P in the known manner to find the desired called line'in the branch ofiice.

In the foregoing description it has been assumed that the switching repeater 'isused in a ten thousand line system, or in a system in which the subscribers, numbers comprise four digits, and that the'branch oflice is not above one thousand lines.' For this reason the switching. repeater must be capable of operating upon the second digit called. \Vhen used in a hundred thousand line system, or in a system in which the subscribers numbers comprise five digits, and the branch. ofiice is not above one thousand lines, it is necessary for the switching repeater to be ca-pable'of operating upon thethird'digit called. For this reason, when operating in a five figure exchange, the relay 73 is relaced by the relays 189 and 190 shownin ig. 7. The conductors 191 and 192 extend to the battery X; the conductors 193 and 194 extend to the release magnet 74; the conductors 195 and 196 extend to the spring 31;

the conductor 197. extends to the bank contact TO and the conductor 1% extends to the contact 173 and multiples thereof. e will suppose that the subscriber to be called, who is in the same brai'urh ollire as the calling subscriber, has the number 5530,01 Upon 4 calling the first digit 5, the wipers oi thev switching repeater will come to rest upon the bank contact .70 and a circiut will be formed, when the private magnet .dei ner gizes, from groiil'ld G? through. the springs 6'7, 68 and 6.9, wiper 65, bankcontact 70, conductor 197, springs 199' and. 200; the upper winding ofrthe relay 189, conductor 194, release magnet 74 and the Springs 165 to battery X. Thereupon the switching repeater will be'released and the relay 1&9 will be locked u over a circuit extending from ground through the springs 29, 30 and 31, condu tor 195, spring 201, lower winding of relay 189 and the conductor 191 to battery A. Upon calling the second digit '5,

the wiper of the switching repeater ,will

come to rest upon the bank contact, and

a circuit will be formed when the private magnet denerg zes from ground Gr through the springs. 67, 68 and 69, wiper 6.5, bank v contact 70, conductor 19?, springs 199 and 202, springs 203and 204, wini'tling of the relay-l90, condhtor 193,, release magnet. 7ft. and the springs 165'to battery X. I 'Thereupon theswit'chlng repeater will be released.

and the relay 100 will be locked up over aclrcuit extending froni ground G? through the sprlngs 29, springs 30 and3'l, conductor 196, springs 205, lower winding of the rela" 190 and the conductor 192 to battery X. The energization of the relay 190 also places ground from ground'G through the springs 206 and 203, springs 202 and 199, conductor 197 to the bank'contact 70. A circuitis also closed from ground G througlr'the'springs 207 and the conductor 198 tothe contact 173 and multiples of'thc same; Upon calling.

the third digit 3, the switching repeater will" come to rest .upon the first idle contact inthe third levelot bank contacts and the switching relay 174 will operate to connect the calling line. with 'a connector iii-that group, as previously explainedw The remainder of the call'and thereleaseof the switches will ay take place in. the manner previously exp'lainedfil, I

While Ihave illustrated my, invention by the. use.of a number inwhichthdfiis ttwo digits are the same, it will" readily seen by any one .versed in the art that by changing the position of the conductors 197 and.

208', .the switching repeater could made to release upon any "combination of the first tivrfdigits called. Furtherrnore,"'wliile. I have illustrated: my. invention m connection with switches o= ...well-known types, it W1ll,

of course, be and that ilfdofpiit able thc'first and second lines to be limited to the exact construction shown and described, but that various changes and modifications will readily suggest themselves to those skilled in the art without departing from the spirit of my inventioi'i. v

I claim,

1. 1. In a telephone system, afi-line', a switch for said line, a second line, a switchingrelay for said switch, means for operating the' switch and for thereby preparing a cir-"l7"5f cuit for said. relay "and for then; releas ing the switch, and means whereby when. the switchis again operated said relayis operated oversaid prepared circuit to eninto connection. y 2. In. a telephone system, .a'line', a progressively movable switch for said line, a" second line, a switching relay for said switch, Ineansfor operating the switch and for thereby preparing a circuit for said 're-J lay and for then releasing the switch, and means whereby.whenthe switch is again operatedsaid relay is operated over said prelines to be brought into. connection.

In a telephone system, a line, a. switch for said line, second line, a switching'relay for said switch, means, involving a magnet anda contact for. operating the switch'and. for thereby preparinga circuitfor said re lay and for then 'relcasingthe sw itch, and means whereby when the switch 1 is againj operated, said relay operated over said f prepared-circuit-to enable the first and sec- 0nd lines-to be brought into connection.

4. In a telephone; system, a line, a switch for said line, a second line, a switching rclay, for said switch, means involving a magnet and a pail-of contacts, for operating 1'05 the switch and. for thereby preparinga c1rcart for said relay and for thenrelea'singf the switch, andmeans; whereby when the swltch .18 again; operated, said relay is op- .eratcd over said Prepared-circuit to enable the first and second lines to be brought into connection. i 1 In a telephone for said line, asec'ond line, a switchingrelay for said switch, meansl involving a mag'hetj1l5 i and a potentialv controller, for operating the switch and for thereby preparing a circuit" for said relay and for then releasing the switch, and means whereby when the switch is again operated said relay is operated over said prepared .circuit to enable "the firstand second llnes to 'bebrought into connection; 6, In atelephone .systenna line, a switch j for said .line, a second .line, .a switching relay "for. said switch, means for operating 1 the switch and for thereby preparing a cir- "(:uit for said relay and for'then releasing the switch, and means, involning a contact," whereby when the switch again operated ,saidi "relay is perated-oyer saidprepered rs'o to bebrough't 80 pared circuit to enable the first and second 90 system a line, a switch circuit to enable the first and secondlines to be brought into connection.

'7'. In telephone system, a line, a switch for said line, a second line, a switching relay for said switch, means for operating the switch and for thereby preparing a clrcuit for said relay and for then releasing the switch, and m'eans involving a magnet and a progressively movable contact, and means whereby when the switch is again operated said relay is operated over said prepared circuit to enable the first and second lines to be brought into connection.

In a telephone system, a line, a switch for said line, a second 1i me, a switching relay for said witch, means, involving a magnet act for adjusting the contact to one of three positions, said means for at ia" the switch and for thereby premg a i" :uit for said relay and for thenreleasing the switch, and means whereby when the switch is again operated said relay is operated over said prepared circuit to enable the first and second lines to be brought into connection.

9. In a telephone system, a line, a switch for said. line, a second line, a switching relay for said switch, means, involving a magnet and a pair of contacts, mechanism for controlling one of said contacts for adjusting the cemlact Jo any one oi three positions, said means for operating the switch and for thereby preparing a circuit for said relay and for then releasing the switcl and means Wherel'iy when the switch is again operated said relay is operated over said prepared circuit tornable the first and second li'ncs to be brought into connection.

1.0. In a telephone system, a line, a switch for said line, a second line, a switching relay for said switch, means, involving a magnet and a circuit controller, for operating the switch and for thereby preparing -a circuit for said r lay and for then releasing the switch, and means whereby when the switch is again operated said relay is operated over said prepared circuit to enable the first and second. lines to be brought into connection.

1.1. In a telephone system, a line, a switch for said line, a second line, a switching relay for said switch. means for operating the switch and for thereby preparing a circuit for said relay, means involving a releasing pawl for then releasing, the switch, and

means whereby when the switch is again operated said relay is operated over said prepared circuit to enable the first and second lines to be brought into connection.

12. In a telephone system, a line, a switch for'said line, a second line, a switching relay for said switch, means for opera ting the switch and for therel iy preparing a. circuit for said relay and for then releasing the switch, and. means, involving a contact and mechanism for adjusting the contact to any one of three positions, whereby when the switch. is again operated said relay is op; erated over said prepared circuit to enable the first and-second lines to be brought into connection.

13. In a telephone system, aline, a switch for said'line, a second line, a switching re lay for said switch, means for operating. the switch and for thereby preparing a circuit for said relay and for then releasing the switch, and means, involving-a progressivel movable contact, whereby, when the switc i is again operated, saidrelay is operated over said prepared circuit to enable the first and second lines to be brought into connection.

14. Ina telephone system, a line, a switch for said line, a shaft, a second line, a switching relay for said switch, means, involving a contact on the shaft and a magnet, for op-' erating the shaft and for thereby preparing a circuit for said relay and'for then releasing the shaft, and means, involving another. contact on' said shaft, whereby when the shaft, is again operated said relay is operated over said prepared circuit to enable the first and second lines to be brought into connection.

. 15. In a telephone system, a line, a second line, a switch for the first line for locating the second line. said switch comprising means for enabling the two lines to be brought into connection after the second line is located, a circuit for controlling said means, means controlled by the switch when operated to prepare said circuit, and means for then releasing the switch whereby when the switch is released and again opera-ted said first means is controlled over said prepared circuit.

16. In a telephone system, a line, a second line, a switch provided with a progressively movable shaft for the first line fior locating the second line, said switch comprising means for enabling the two lines to be brought into connection after the second line is located, 'a, circuit for controlling said means, means controlled by the switch, through-a contact on said shaft, when ope-1'- ated to prepare said circuit and means for then releasing the shaft whereby when the shaftis released and again operated said first means is controlled over said prepared circuit and'over another contact ,on. the shaft.

able shaft, contact makers on said shaft, a release mechanism associated with said shaft, contacts associated with said contact'makers, circuits extending therefrom, a line connected with said switch, switching means for connecting said line with some of said contact makers, a magnet for controllingsaid switching means, a circuit for said magnet, means for operating said progressively movable shaft and for releasing the same and for at the smile time preparing the circuit of said switching magnet, whereby when the switch is again operated said line may be,

extended to said contact makers.-

19. In an automatic telephone trunking system, a trunkmg'switch provided with a progressively movable contact maker, a release mechahism associated with said switch,

a contact associated with said contact maker, i

said release mechanism comprising a magnet for controlhngthe said mechanism, a circuit for said magnet including said contact maker, another contact, acircuit for applying a potential to said'cont'act, a switch in said last circuit for controlling the same, and n'icansassociated with said first contact for operating said switch.

"20. In a telephone system, a switch with a progressively movable contact maker, a line associated with said sWitch,-an impulse sending device for sending a plurality of sets of impulses to operate said switch to connect said line with another line, a mechanism associated with said contact maker for releas ing the same, means for advancing the contact maker and for then operating the re lease mechanism to restore the contact maker before the connection 18 completedin re spons'c tothe first set of impulses, and for operating the switchin IGSPOllSetO the remaining series of impulses to complete the connection;

21. In a telephone system, a line, a switch for said line, a second line, a switching relay for said switch, means for operating the switch. and'for thereby preparing a circuit for said relay, and for then releasing'thc switch, said means involving a magnet and a bodily movable contact controlled'by mec'l'ianism for adjusting said contact to any one of a plurality of. positions, and means whereby when the swltch is again operated the said relay is operated over said prepared circuit brought into connection. t a

22. In a telephone system, a line, a switch for said lii'1:c,a second lineya switching relay for, said switch, means for operating the switch and for thereby preparing a circuit for said relay and forthen releasing the switch, said. means involving a magnet and a pair of contacts, one of which contacts'be ing bodily movable and controlled by mechato enable the'first and second lines to be nism for adjusting" thesaid movable'contact llty of positions, and" to anyone of a f means whereby when said switch is again operated, said relayis operated over said prepared circuit to enable the first and second lines to be brought into cornicction.

23. In a-telephone system, a line, switch second lines to be brought into connection,

all of said means including movable contact makers for engagingstationaiy contacts, lines terminating in said stationary contacts, busy test circuits associated with'said lines, means resprmsive, when the switch is last operated, for moving said makers into engage ment with one of said lines and if the line is busy, for automatically advancing the con-- tact makersthrough the instrumentality of the corresponding busy test circuit onto the next line. i

24. In a telephone systenna line, a progressivcly movable switch for said line, a second line, a switching relay for said switch, means for operating the switch and for thereby preparing a circuit for. said relay for said line, a second line,

in said stationary contacts, busy including and for then releasing the switch, means whereby when the switch is againoperated said relay is operated over said prepared circuit to enable the first and second lines to be brought into connection, all Of said means including movable contact makers for en 31a glng stationary contacts, lines terminating associated with said lines, means responsive, when the switch is last operated, for mov ng 1 said makers'into engagement with one oi' said lines and the line is busy, for automatically advancing the contact Isak s through the instrumentality of the corr sponding busy test circuit onto the next line. v 2 5.. In a telephone system,a line, a switch a switching rciay for said switch, means involving afmagnet and a contact, for-operating the switch and for thereby preparing a: circuit for said relay;

and for then releasing the switch, means whereby when the switch 15 agam operated,

said relay is operated over said prepared circuit to enable the first and second lines tobe brought into connection, all of saidmeans ovable contact makers for engaging stationaryconta' ts, linesterminatin associated with said-line, means responsive when; tlieswitchis last operated, for moving said makers into engagementlwith one of 1 through the Iinstrumcntality of? the correspondingbus test circuit onto the next line.

i 26. In a te ephone system, 1 a line, aswitch test circuits "In said stationary conta'c, s, busyltest circuits i for said line, a second line, a switching relay for said switch, meansinvolving a magnet and a pair of contacts, for operating. the switch and foi' thereby preparing a circuit for said relay and for then releasing the switch, means whereby when the switch is again operated said relay is operated over said prepared circuit to enable the first and second lines to be brought-into connection, all of said means including movable contact .makers for engaging stationary contacts,

lines terminating in said stationary contacts, busy test circuits associated with said lines, meansresponsive, when the switch is last operated, for moving said makers into en: gagement with'one of 'said lines and if the line is busy, jfor automatically advancing the contact makers through the instrumentality of the corresponding busy test circuit. onto the ne xt line.

2, 7. In a telephone system, a line, a switch a for said line, a second line, a switch relay for said switch, means involving a magnet and a potential controller, for operating-the switch and forvthereby preparing a circuit for said relay and for then releasing the switch, means whereby when the switch is again operated said relay is operated over said prepared circuit to enable the first and second lines to be brought into connection.

. all of said means including movable contact makers for engaging stationary contacts. lines terminating in said stationary contacts, busy test circuits associated 'with said lines, means responsive when the switch is last operated, for moving said makers into engagement with. one of said lines andit the line is busy, ,for automatically advancing the contact makiers through the instrumentality 0t the'fcorresponding-busy test circuit onto the next line. 1

60 onto the next line.

28. In a telephone system, a line, a switch for said line, asecond line, a switching relay for said switch, means for operating the switch and for thereby preparing a circuit for said relay, means for then releasing the switch, means whereby when the switch. is

again operated said relay is operated over said prepared circuit to enable the first and second lines'to be brought into connection, all ofsaid means including movable contact makers for engaging stationary contacts,

lines terminating inysaid stationary contacts, busy test circuits associated with said lines, means responsive, when the switch is last operated, formoving said makers into engagement with one ,of said lines and: if. the line isbusy foreautomatically advancing thecontact makers through the instrumentality of the'corresponding-busy test circuit v for-said line, a second line, a switching re- "lay for said switch, means involvingiamag- 29. In a telephone system,-a -l ine, a switch for said line, a second line, a switching relay for said-switch, means for operating the switch and for thereby preparing a circuit associated with said lines, me when the SWIM-ll is last operated, for moving said makers into engagement with one of 120- ing: contact o for said relay and for then releasing the switch, means, involving a contact, whereby when the switch is again operated said relay 7 is operated over said prepared circuit to enable the first and second lines to be brought into connection, all of said means including movable contact makers for engaging stationary contacts, lines terminating in said stationary contactsfbusy test circuits associated with said lines, means responsive, when the switch is last operated, for moving said makers into engagement with one of said lines and if the line is busy, for automatically advancing the contact makers through the instrumentality of the corresponding busy test circuit onto the next line. a r 30. In a telephone system, a line, a switch for said line, a switching relay for said switch, means for ope'ratingthe switch and for thereby'preparing a circuit for said relay and for then releasing the switch, said means involving a magnet and a progressively movable contact, means whereby when the switch is again operated. said relay is operated over said prepared circuit to enable the first and second lines' to be brought into connection, movable contact makers for said switch for engaging stationary contacts, lines terminating 'in said stationary contacts, busy test circuits associated wit said lines, means resprjnsive. when the switch is last operated, for moving said maker's intoengagement with one of said lines and if the line is busy, for automatically advancing the contact makers through the instrumentality of the and a contact controlled by mec anism for adjusting the contact to any oneof three positions, for operating theswitch and for thereby preparing a circuit for said relay and for then releasing the switch, means whereby 'hen the switch is again operated said relay is operated over said )repared circuit to enable the first and sec-on lines to be brought into connection, all of said means including movable contact makers for engaging stationary contacts, lines terminating in said stationary contacts, bus test circuits s responsive,

said lines and if the line is busy, for anti matically. advancing the contact makers I through the instrumentality of the cor:

sponding busy test circuit onto the next line.

32. In a telephone system, aljne, a switch 7125 net and 'apair of contacts, one of wh ch tacts is con ro le by mm k q l i l I -tions, for operating the, switch andfo I thereby preparing a circuit for, said relay and for. then releasing the switch, means whereby when the switch is again operated said relay is operated over said prepared circuit to enable the first and secondlines brought into connection, all of said means including movable contact markers for? engaging stationary contacts, lines teri0 'minating: in said stationary contacts, busy test circuits associated with said lines, means responsive, when the switch is last operated, for moving said makers into engagement with one of said lines and if the line is busy,

for" automatically advancing the contact makers through the instrumentality of the cor-responding busy test circuit onto the next line. i

33. In a'telephone system, a line, a switch for said line, a secondline, a switching i'c layafor said switch, means, involving a niagnetva-nd a'circuit controller, for operating the switch and for thereby preparing a circuit for said relay and for then releasing the switch, meansivliereby"wlien the switch is againoperated sa d relay is operated over Jsaid prepared circuit to enable-the first and secondlines tobe brought into connection, all of said means including movable contact makers for engaging stationary contacts,

lines terminating in said stationary contacts, busy test circuits associated with said lines. means ,iespoiisive, whcn the switch is last operated f'or moving said makers into ongageinentwith one of said'lines, and if the line isbus'y, for a' itoiiiatically a'di'aiicing the contact makers through me iiistriiiiientality of the corresponding busy test circuit onto the next line. i

40 34 In a tcle 'ihoiie system, a line, a switch for "said line, asccon'd liiie. a mvlttlilng rclay for saidswitch, means for o xii ating the switch and for. thereby pi'e 'iaringa circuit for said relay, means involving a releasing 4 5 pawl for then releasing the switch, and

means whereby when the switch is again operated said relay is operated ftivei: said prepared circuit to enable the first and second lines to bebroiight into connection, all of 0 said means including movable contact makers for engaging stationary contacts, lines terminating in said stationary contacts, busy test circuits associateiil with said lines, means responsive, when the switch is last operated,

fjorn ioving said makers 'intoengagement with one of said'lines and if the line is busy for automatically advancing the contact makers through the instrumentality of the corresponding busy test circuit onto the next line." Y

'35. In a tdle'phone system, a lineda switch for said'line', a second line, a switching relay for said, switch, means for onerating the i switch and; for thereby preparing a circuit for said relay and for then releasing the 'matically advancing the contac through the instru nentality of tie corre' sms switch, and means, involvinga contact controlled by Inechanism'for adjusting the contact to any one of three positions, whereby when the switch is again operated said relay is operated. oversaid prepared circuit to en" able the first and second lines to be brought into connectionjall of said means including movable contact makers for engaging stationary contacts, lines terminating in said stationarycontacts, busy test circuits associated with said lines, means, responsive, when the switch 'is last operated, for moving said makers into "engagement with oneof said lines andif the line is busy, for automakers sponding busy test circuitonto the next line.

7 36.' Ina telephoi'ie system, a line, a switch lay for said switch, means for operating the switch and for thereby preparing a circuit for said line, a second line, a switpliing rea said relay and for then releasing the switch, and means, involving an regressively movable contact, whereby en the switch is again operated saidrelay is opcrated over "said prepared circuit, to enable the first and second lines tobe brought into connection, all of said means including movable conta ct makers for engaging stationary contacts, lines terniiniiting in said stationar contacts, busy test circuits associated wit said lines, means iesponsive, when the switch is last operated, for moving said makers into engagement with one of said linesand if the line is busy, for automatically advancing the contact makers through the instrumentality of the. corresponding busy testcircuit onto the next line. i y

37. In a telephone system, a line, a switch for said linc,'.a shaft, a SBGQIId-llTIB, a switching relay for said switch, means,,involving a contact on the shaft and a magnet, for opc'i'a ting the shaft and for thereby preparlllg a, circuit for said relay and for then releasing the shaft, and means, involving another contact on said shaft, whereby when theshaft is again operated said'relay isoperated over said prepared circuit to enable the firstandsecoiid lines to be brought into connection, all of said means including mov able contact makers 'for engaging stationary contacts, lines terminating insaid stationary contacts, busy testcircuits-associated with, said'lines, means responsive, when the switch is last operated, 'for moving said makers into, engagement with one of said linesand if the line is busy, for automaticall adi ancing the contact "makers through t e in-x strumentality of the corresponding busytest circiiit'onto the next line. l v

38. In a telephonesystem, a line,-'a second line, aswitch for the first line for 10- cating the second line, said switch comprising means for enabling the two lines to be brought into connection after the second line operated to prepare said circuit, and means for then releasing the switch whereby when the switch is released and again operated said first means is controlled over said prepared circuit, all of said -.means including movable contact makers for engagingstm tionary contacts, lines terminating in said stationary contacts, busy test circuits associated with said lines, means responsive, when the switch is last operated for moving said IIliLk ers into engagement with one of said lines and if the line is busy for automatically advancing the contact makers through the instrumentality of the corresponding busy circuit onto the next line. I i

39. In a telephone system, a line, a second.

' line, a switch provided with a progressively movable shaft for the first line for locating the second line, said switch comprising, means for e11al)li11g.tl1.e two lines to he brought into connection after the second line is located, a circuit'for controlling said means, means controlled by the switch, through a contact on said shaft, when operated, to prepare said circuitand means for then releasing the shaft whereby when the: shaft is released and again operated said first means is controlled over said prepared circuit and over another contact on the shaft, all of said means including movable contact makers for engaging stationary contacts, lines terminating in said stationary contacts, busy test circuits associated with said lines means responsive, when the switch is last operated, for moving said makers into engagement with one of said linesand if the line is busy, for automatically advancing the contact makers through the instrumentality of the corresponding busy test circuit onto the next line.

40. In a telephone system, a line, a second line, a switch for said first line, an auxiliary switching mechanism associated with said switch, a magnet for controlling said auxiliary switching mechanism, said switch being provided with means for movingthe switch to prepare the circuit of said magnet, means for then releasing the switch and for again operating the switch to locate the second line and to operate said magnet to enable the first and second lines to be con net-ted, movable contact makers for said tality of the corresponding test circuit onto the next line.

41. In an automatic telephone system, a.

over said prepared circuit to enable switch provided with a progressively able shaft, contact makers on said sn release mechanism associated with said contacts associated with said contact 11 ers, circuits extending therefrom, a line cor I nected with said switch, switching mcalw for connecting said line with some of said. contact makers, a magnet for. controlling said switching means, a circuit for said. mag

net, means for operating said progressively movable shaft and for releasing the same and for at the same time preparing the circuitof said switchin magnet, whereby when the switch on (illtl'tlied, said line may be extended to said contmrt makers, lines terminating in said st: busy test circuits ti iltflflill'm means rcspoa' when the last opera-lied. tor moi aid. engagementwith one of said liUIo line is busy, for automatically. the contact makers through the tality of the corrcspomling busy ii. onto the next liue.-

42. In a telephone system, a line, a switch for said line, a second. line, a switc g relay for said switch, means for (1})911111.

forsaid relay and for then re: 1511' switch, and means whereby when to 15 again operated said relay the *ch e first and second lines to be brought into conned tion. said first means comprising also a device for maintaining the circuit of said relay in its prepared condition 6 iris interval between the releasing of the in the first instance and the operation. or switch thereafter.

FL in a telephone system, a for said line. a set-mid line, a an layior said switch, means, invoiving a net and a contactfir operating the-swit and for thereby pr aring a circuit a. relay and for then releasing the swii a, means whereby when the switch again operated said relay is operated over'said prepared circuit to enable the first and second lines to be brought into connection, said first means comprising also a device for maintaining the circuit of said relay in its prepared condition during the interval between the releasing of the switch in the first instance and the operation of the switch thereafter. a, i A

44. In a telephone system, a' line, a switch for said line, a second line, a switching relay for said switch, means involving a mag net and a air of contacts, for operating the switch and for thereby preparing a circuit for said relay and focthen releasing the switch. and means whereby when the switch is. again operated. said relay operated over said prepared. circuit to enable the irst and second lines to be brought into conneci the r switch and for thereby preparing a circuit 

